The proliferation of wired and wireless technologies has given rise to the possibility of multi-access options for mobile, multi-homed hosts. Enabling multi-access techniques improves fault tolerance by adding redundancy to network connections. For example, if a host is enabled with two network interfaces connected to the Internet via two different Internet service providers (ISPs), the failure of one network will not stop data transmission. The host will be capable of continuing the data transfer by switching over to the other network. Furthermore, if both networks are active at the same time, but packets experience higher delay and congestion on one path, multihoming facilitates the possibility of switching over to the network path offering better performance. However, the key factor in attaining the benefits of multihoming is to ensure that the handoff or switch over from one network interface (or a network path) to the other active interface should take place with minimal interruption. Stream control transmission protocol (SCTP) provides support for multihoming by allowing a single connection between two nodes to hold several IP addresses simultaneously.
Key Terms in this Chapter
Network: In information technology, a network is a series of points or nodes interconnected by communication paths. Networks can interconnect with other networks and contain sub-networks.
Multi-Homed: Multi-homed describes a computer host that has multiple IP addresses to connected networks. A multi-homed host is physically connected to multiple data links that can be on the same or different networks.
Reliability: Reliability is an attribute of any computer- related component (software, hardware, or a network, for example) that consistently performs according to its specifications.
MTU: A maximum transmission unit (MTU) is the largest size packet or frame, specified in octets (eightbit bytes), that can be sent in a packet- or frame-based network such as the Internet.
Protocol: A protocol is a special set of rules that end points in a telecommunication connection use when they communicate.
Packet: A packet is the unit of data that is routed between an origin and a destination on the Internet or any other packet-switched network.
Fragmentation: In TCP/IP, fragmentation refers to the process of breaking packets into the smallest maximum size packet data unit (PDU) supported by any of the underlying networks.
SCTP (Stream Control Transmission Protocol): A protocol for transmitting multiple streams of data at the same time between two end points that have established a connection in a network.
NAT (Network Address Translation): Translation of an Internet protocol address (IP address) used within one network to a different IP address known within another network. One network is designated the inside network and the other is the outside.
Cookie: A cookie is information for future use that is stored by the server on the client side of a client/server communication.